Purpose: Research on follow-up and locator methods for substance abuse offenders is generally limited (Anglin, 1986). The lack of information exists partially because conducting longitudinal research is an arduous task which involves many hours of labor with a mobile population. The purpose of this presentation is to discuss locator strategies and recommend approaches that investigators can use during study planning and implementation.

Methods: Two longitudinal studies involving substance abusing offenders used locator strategies presented in this paper. These strategies included regular jail/prison checks, phone calls, online inmate searches, home visits, and mailings. One study focused on health and health services use and involved 721 prisoners and included a follow-up one year after their release from prison. The second study focused on employment issues among participants in two Kentucky Drug Court programs with interviews at 12, 18, and 24 months after program entry.

Results: These locator strategies produced a 92% follow-up rate for the prison study with a 90% follow-up rate for the employment study. With these populations, the most effective location method was the use of online inmate systems. In both rural and urban areas the second most effective location method was phone calls. However, it became evident through the course of the study that differences exist between rural and urban populations which suggest that these populations should be located using different methodologies.

Implications for practice: In order to achieve an effective longitudinal study and increase internal validity, 80% or more of the baseline subjects should be considered as the target for follow-up interviews. Using planned strategies can help attain this goal. Location methods should be of particular interest to social work researchers in order to track and locate subjects for follow-up.